Micrograms to Milligrams Converter

Convert mcg to mg and back. A milligram is 1000 micrograms, so this is a simple move of the decimal, handy for reading supplement and medicine labels.

Micrograms ⇄ Milligrams
mcg
=
mg
Result500 mcg = 0.5 mg
Quick answer
A milligram is 1000 micrograms, so to convert mcg to mg divide by 1000, and to go back multiply by 1000. That makes 500 mcg equal to 0.5 mg and 1000 mcg equal to 1 mg. mcg, µg and microgram all mean the same unit, which matters on supplement labels where the symbols are mixed.

Conversion table (micrograms to milligrams)

MicrogramsMilligrams 
25 mcg0.025 mgvitamin D 1000 IU
50 mcg0.05 mg
100 mcg0.1 mg
250 mcg0.25 mg
400 mcg0.4 mgfolic acid
500 mcg0.5 mg
1000 mcg1 mgequals 1 mg
2500 mcg2.5 mg
5000 mcg5 mg

How to convert mcg to mg

mg = mcg ÷ 1000reverse: mcg = mg × 1000 · mcg = µg = microgram
mcg
micrograms you enter (also written µg)
mg
the result in milligrams
1000
micrograms in every milligram

Both units are metric, so the conversion is exact: shift the decimal three places. 1250 mcg is 1.25 mg, and 0.3 mg is 300 mcg.

This tool is for reference only and is not medical advice. Always follow the dose on the label or from your doctor or pharmacist.

Frequently asked questions

How many mcg are in a mg?

One milligram contains 1000 micrograms.

Is mcg the same as µg?

Yes. mcg, µg and microgram are three ways of writing the same unit. "mcg" is preferred on labels to avoid misreading the µ symbol.

How many mg is 1000 mcg?

1000 mcg is exactly 1 mg.

Is 500 mcg the same as 0.5 mg?

Yes, 500 mcg equals 0.5 mg.

What is 5000 mcg in mg?

5000 mcg is 5 mg.

How do I convert mcg to IU?

That depends on the substance, since IU is defined separately for each. Use the mcg to IU page and pick your vitamin.

Related conversions

Reading a vitamin label? mcg to IU handles vitamins D, A and E, where the IU value depends on the exact form. For a liquid medicine, mg to cc and mcg to mL turn a dose into a volume once you know the concentration. And for a blood-test result, mmol/L to mg/dL covers glucose and cholesterol. None of these replace a clinician's instructions.

Quick facts
1 milligram
1000 mcg
1 microgram
0.001 mg
mcg
= µg = microgram
Measures
Mass